ABSTRACT
Objective@#To establish a method for the determination of 1-methoxy-2-propanol in urine using headspace solid phase micro-extraction coupled with gas chromatography.@*Methods@#The 1-methoxy-2-propanol was enriched by headspace solid phase micro-extraction fiber coated with carbene/polydimethylsiloxane (CAR/PDMS) . Single factor rotation method was used to optimize the conditions of extraction temperature, salt amount, and extraction time. The separation was performed on DB-5 (30 m×0.32 mm×0.25 μm) capillary column and detected with flame ionization detector. The quantification was based on the standard curve.@*Results@#The concentration of 1-methoxy-2-propanol in urine was linear in the range of 0.50-10.0 mg/L, and the linear correlation coefficient was 0.9993. The detection limit of the method was 0.14 mg/L, and the limit of quantification was 0.45 mg/L. The recovery was 85.8% to 104.7%, and the RSD of intra- and inter-batch precision were 3.25%-6.65% and 0.81%-3.96%, respectively.@*Conclusion@#The method is high sensitivity and simple operation, and is suitable for the determination of 1-methoxy-2-propanol in urine of occupational exposure population.
ABSTRACT
Objective To explore the effects of atmospheric haze and air pollutants(PM10, PM2.5), SO2, NO2 on hospital visits for cardiovascular diseases. Methods The relationship among atmospheric haze, air pollution and the outpatients data of Guangzhou for cardiovascular disease had been investigated by collecting the air pollution data, the meteorological data and cardiovascular diseases’ outpatients data in Guangzhou city from January 1, 2006 to December 31,2008 . The time-series analysis by auto-regression model was used, controlling for long -term trends, seasonal patterns and meteorological variables. Results Auto-regression model showed that the number of outpatients in 2008 was higher than that in 2006.The number was larger in April and December compared with that in January, and it was higher on Monday, Tuesday, Wednesday, Thursday and Friday than on Saturday, Sunday. There was a positive correlation between the haze level and cardiovascular outpatients. The number of hospital outpatients increased by 2.12 units with each additional day of the atmospheric haze. The haze level (lag2) of the former second day had a negative impact on the intraday data of outpatients. The residual parts showed that outpatients’ residual data (AR1, AR3) of the former first and third day had a positive effect on intraday outpatients’ residual data (increased by 52.25%, 26.1%), while the outpatients’ residual data of the former second day (AR2) had a negative effect on outpatients’ residual data of the present day (decreased by 17%). In addition, a variety of air pollutants (PM10, PM2.5, SO2, and NO2) showed some positive correlation, and had hysteresis. Conclusion The atmospheric haze, generated from suspended particulate, meteorological factor and gaseous pollutants, is the environmental pathogenic factor for the cardiovascular diseases, while the effects of single air pollutant on the hospital visit for cardiovascular diseases can be weakened by the haze pollution.